Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-08-29T14:02:13Z No. of bitstreams: 1 2009 - Breno Almeida Soares.pdf: 7105040 bytes, checksum: 3b6aebf34151816545510b0506ed3412 (MD5) / Made available in DSpace on 2017-08-29T14:02:13Z (GMT). No. of bitstreams: 1 2009 - Breno Almeida Soares.pdf: 7105040 bytes, checksum: 3b6aebf34151816545510b0506ed3412 (MD5) Previous issue date: 2009-09-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior, CAPES, Brasil. / This work is part of a research project which investigates the utilization of abundant and accessible natural products in the synthesis of new molecules with potential activity against Chagas? disease. Recent studies carried out in our laboratory showed activity against Trypanosoma cruzi for piperine, a major component of Piper nigrum and for a series of its derivatives and analogues. Using bioisosterism as a strategy for molecular modification, we describe here the design, synthesis and antiparasitic evaluation of class of derivatives of 1,2,4-oxadiazole. The key step of the synthetic strategy used involved the SNAC reaction of the benzamidoxima with acid chlorides followed by cyclization, which allowed the preparation of eight new 1,2,4-oxadiazole The evaluation of the toxic activity of these new derivatives against epimastigote form of T. cruzi confirmed the bioisosteric relationship between the natural amide and the new products prepared, showing the oxadiazole 55 direct derived from piperine, as the most active compound in the series. / Este trabalho se insere numa linha de pesquisa que visa a utiliza??o de produtos naturais abundantes e access?veis na s?ntese de novas mol?culas com potencial atividade anti-chag?sica. Estudos recentes em nosso laborat?rio demonstraram a atividade antiparasit?ria da piperina e de uma s?rie de derivados e an?logos sobre o Trypanosoma cruzi, agente etiol?gico da doen?a de Chagas. Utilizando o bioisosterismo como estrat?gia de modifica??o molecular, descrevemos aqui o planejamento, a s?ntese e a avalia??o antiparasit?ria de derivados da classe dos 1,2,4-oxadiaz?is. A etapa-chave da estrat?gia sint?tica utilizada envolveu a rea??o de SNAC da benzamidoxima com cloretos de ?cidos, seguida de cicliza??o, que permitiu a prepara??o de oito novos 1,2,4- oxadiaz?is. A avalia??o da atividade t?xica destes novos derivados contra a forma epimastigota do T. cruzi confirmou a rela??o bioisost?rica entre a amida natural e os novos derivados preparados, evidenciando o oxadiazol 55 derivado direto da piperina, como o composto mais ativo da s?rie.

Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2018-04-11T16:32:51Z No. of bitstreams: 1 2010 - Jaci de Almeida.pdf: 1762363 bytes, checksum: 6b47b0e954a40b42efe066ff6875b0af (MD5) / Made available in DSpace on 2018-04-11T16:32:51Z (GMT). No. of bitstreams: 1 2010 - Jaci de Almeida.pdf: 1762363 bytes, checksum: 6b47b0e954a40b42efe066ff6875b0af (MD5) Previous issue date: 2010-12-10 / Ectoparasite affects in the animals, carrying great prejudices to the health and considerable economic losses. Antiparasitic utilization of wide action spectrum has been assisting in the losses reduction in consequence of these infestations. They were objectives of this work, evaluate of the treatment antiparasitic effects, in therapeutic doses, in the preventive control of the natural infestations for Dermatobia hominis and Haematobia irritans, and about the andrological characteristics, enzymatic profile (AST and ALT) and her correlations in Nelore bulls seminal caracteristics. They were used 20 bulls from 24 to 30 age months, managed in grazing system (Brachiaria decumbens and B. brizantha). The experiment was executed in completely randomized design with four treatments (T1 = Control, without medication; T2 = Ivermectina injet?vel to 3,15%; T3 = Fipronil ?pour-on? e T4 = Doramectina to 1%), three applications (0, 60 and 120 days), five repetitions (bulls) and five semen collections (D0, D15, D30, D45 and D60). The animals were submitted to andrological examinations biweekly inside the periods, being evaluated the ponderal, testicular and seminal characteristics, and the enzymatic profiles. In the statistical analyses were used Anova and comparisons between averages according to de Kruskal-Wallis e Bonferroni Tests in the GraphPad Prism? vers?o 4.0 to Windows?. The obtained results indicate that (a) the antiparasitic treatments used in the preventive control in the natural infestations of ectoparasites do not influence negatively the ponderal and reproductive characteristics, and (b) the enzymes analyses AST and ALT, in the sanguine serum, evidenced do not be efficient methodology for evaluation of Nelore bull spermatogenesis implication. The prophylactic application of the antiparasitic drugs, in the pre-breeding season, in bulls created extensive is an efficient technique of ectoparasitism natural control to D. hominis and H. irritans, being the product choice be entailed to the application practicability and to the cost in each region. / Os ectoparasitas afetam os animais, acarretando grandes preju?zos a sa?de e consider?veis perdas econ?micas. A utiliza??o de antiparasit?rios de amplo espectro de a??o tem auxiliado na redu??o de perdas em decorr?ncia dessas infesta??es. Foram objetivos desse trabalho, avaliar os efeitos dos tratamentos antiparasit?rios, em doses terap?uticas, no controle preventivo da infesta??o natural por Dermatobia hominis e Haematobia irritans, sobre as caracter?sticas androl?gicas, perfil enzim?tico (AST e ALT) e correla??es nas caracter?sticas seminais de touros Nelore. Foram utilizados 20 touros de 24 a 30 meses de idade, criados a pasto (Brachiaria decumbens e B. brizantha). O experimento foi executado em delineamento inteiramente casualizado com quatro tratamentos (T1 = Controle, sem medica??o; T2 = Ivermectina injet?vel a 3,15%; T3 = Fipronil ?pour-on? e T4 = Doramectina a 1%), tr?s aplica??es dos tratamentos (0, 60 e 120 dias), cinco repeti??es (touros) e cinco coletas de s?men (D0, D15, D30, D45 e D60). Os animais foram submetidos a exames androl?gicos quinzenais dentro dos per?odos, sendo avaliadas as caracter?sticas ponderais, testiculares, seminais e perfil enzim?tico. Nas an?lises estat?sticas foram utilizados Anova e compara??es entre m?dias de acordo com os testes de Kruskal-Wallis e Bonferroni no programa GraphPad Prism? vers?o 4.0 para Windows?. As an?lises dos resultados obtidos indicam que (a) os tratamentos antiparasit?rios empregados no controle preventivos na infesta??o natural de ectoparasitos n?o influenciam negativamente as caracter?sticas ponderais e reprodutivas, e (b) as an?lises das enzimas AST e ALT, no soro sangu?neo, evidenciaram n?o ser metodologia eficiente para avalia??o de comprometimento da espermatog?nese de reprodutores bovinos da ra?a Nelore. A aplica??o antiparasit?ria profil?tica, na pr?-esta??o de monta, em touros criados extensivamente ? uma t?cnica eficiente para o controle de ectoparasitismo natural por D. hominis e H. irritans, devendo a escolha do produto estar vinculada ? praticidade de aplica??o e ao custo em cada regi?o.